dasd_fba.c

linux-2.6.15.6

/* 
 * File...........: linux/drivers/s390/block/dasd_fba.c
 * Author(s)......: Holger Smolinski <[e-mail]>
 * Bugreports.to..: <[e-mail]>
 * (C) IBM Corporation, IBM Deutschland Entwicklung GmbH, 1999,2000
 *
 * $Revision: 1.40 $
 */

#include <linux/config.h>
#include <linux/stddef.h>
#include <linux/kernel.h>
#include <asm/debug.h>

#include <linux/slab.h>
#include <linux/hdreg.h>	/* HDIO_GETGEO			    */
#include <linux/bio.h>
#include <linux/module.h>
#include <linux/init.h>

#include <asm/idals.h>
#include <asm/ebcdic.h>
#include <asm/io.h>
#include <asm/todclk.h>
#include <asm/ccwdev.h>

#include "dasd_int.h"
#include "dasd_fba.h"

#ifdef PRINTK_HEADER
#undef PRINTK_HEADER
#endif				/* PRINTK_HEADER */
#define PRINTK_HEADER "dasd(fba):"

#define DASD_FBA_CCW_WRITE 0x41
#define DASD_FBA_CCW_READ 0x42
#define DASD_FBA_CCW_LOCATE 0x43
#define DASD_FBA_CCW_DEFINE_EXTENT 0x63

MODULE_LICENSE("GPL");

static struct dasd_discipline dasd_fba_discipline;

struct dasd_fba_private {
	struct dasd_fba_characteristics rdc_data;
};

static struct ccw_device_id dasd_fba_ids[] = {
	{ CCW_DEVICE_DEVTYPE (0x6310, 0, 0x9336, 0), driver_info: 0x1},
	{ CCW_DEVICE_DEVTYPE (0x3880, 0, 0x3370, 0), driver_info: 0x2},
	{ /* end of list */ },
};

MODULE_DEVICE_TABLE(ccw, dasd_fba_ids);

static struct ccw_driver dasd_fba_driver; /* see below */
static int
dasd_fba_probe(struct ccw_device *cdev)
{
	int ret;

	ret = dasd_generic_probe (cdev, &dasd_fba_discipline);
	if (ret)
		return ret;
	ccw_device_set_options(cdev, CCWDEV_DO_PATHGROUP);
	return 0;
}

static int
dasd_fba_set_online(struct ccw_device *cdev)
{
	return dasd_generic_set_online (cdev, &dasd_fba_discipline);
}

static struct ccw_driver dasd_fba_driver = {
	.name        = "dasd-fba",
	.owner       = THIS_MODULE,
	.ids         = dasd_fba_ids,
	.probe       = dasd_fba_probe,
	.remove      = dasd_generic_remove,
	.set_offline = dasd_generic_set_offline,
	.set_online  = dasd_fba_set_online,
	.notify      = dasd_generic_notify,
};

static inline void
define_extent(struct ccw1 * ccw, struct DE_fba_data *data, int rw,
	      int blksize, int beg, int nr)
{
	ccw->cmd_code = DASD_FBA_CCW_DEFINE_EXTENT;
	ccw->flags = 0;
	ccw->count = 16;
	ccw->cda = (__u32) __pa(data);
	memset(data, 0, sizeof (struct DE_fba_data));
	if (rw == WRITE)
		(data->mask).perm = 0x0;
	else if (rw == READ)
		(data->mask).perm = 0x1;
	else
		data->mask.perm = 0x2;
	data->blk_size = blksize;
	data->ext_loc = beg;
	data->ext_end = nr - 1;
}

static inline void
locate_record(struct ccw1 * ccw, struct LO_fba_data *data, int rw,
	      int block_nr, int block_ct)
{
	ccw->cmd_code = DASD_FBA_CCW_LOCATE;
	ccw->flags = 0;
	ccw->count = 8;
	ccw->cda = (__u32) __pa(data);
	memset(data, 0, sizeof (struct LO_fba_data));
	if (rw == WRITE)
		data->operation.cmd = 0x5;
	else if (rw == READ)
		data->operation.cmd = 0x6;
	else
		data->operation.cmd = 0x8;
	data->blk_nr = block_nr;
	data->blk_ct = block_ct;
}

static int
dasd_fba_check_characteristics(struct dasd_device *device)
{
	struct dasd_fba_private *private;
	struct ccw_device *cdev = device->cdev;	
	void *rdc_data;
	int rc;

	private = (struct dasd_fba_private *) device->private;
	if (private == NULL) {
		private = kmalloc(sizeof(struct dasd_fba_private), GFP_KERNEL);
		if (private == NULL) {
			DEV_MESSAGE(KERN_WARNING, device, "%s",
				    "memory allocation failed for private "
				    "data");
			return -ENOMEM;
		}
		device->private = (void *) private;
	}
	/* Read Device Characteristics */
	rdc_data = (void *) &(private->rdc_data);
	rc = read_dev_chars(device->cdev, &rdc_data, 32);
	if (rc) {
		DEV_MESSAGE(KERN_WARNING, device,
			    "Read device characteristics returned error %d",
			    rc);
		return rc;
	}

	DEV_MESSAGE(KERN_INFO, device,
		    "%04X/%02X(CU:%04X/%02X) %dMB at(%d B/blk)",
		    cdev->id.dev_type,
		    cdev->id.dev_model,
		    cdev->id.cu_type,
		    cdev->id.cu_model,
		    ((private->rdc_data.blk_bdsa *
		      (private->rdc_data.blk_size >> 9)) >> 11),
		    private->rdc_data.blk_size);
	return 0;
}

static int
dasd_fba_do_analysis(struct dasd_device *device)
{
	struct dasd_fba_private *private;
	int sb, rc;

	private = (struct dasd_fba_private *) device->private;
	rc = dasd_check_blocksize(private->rdc_data.blk_size);
	if (rc) {
		DEV_MESSAGE(KERN_INFO, device, "unknown blocksize %d",
			    private->rdc_data.blk_size);
		return rc;
	}
	device->blocks = private->rdc_data.blk_bdsa;
	device->bp_block = private->rdc_data.blk_size;
	device->s2b_shift = 0;	/* bits to shift 512 to get a block */
	for (sb = 512; sb < private->rdc_data.blk_size; sb = sb << 1)
		device->s2b_shift++;
	return 0;
}

static int
dasd_fba_fill_geometry(struct dasd_device *device, struct hd_geometry *geo)
{
	if (dasd_check_blocksize(device->bp_block) != 0)
		return -EINVAL;
	geo->cylinders = (device->blocks << device->s2b_shift) >> 10;
	geo->heads = 16;
	geo->sectors = 128 >> device->s2b_shift;
	return 0;
}

static dasd_era_t
dasd_fba_examine_error(struct dasd_ccw_req * cqr, struct irb * irb)
{
	struct dasd_device *device;
	struct ccw_device *cdev;

	device = (struct dasd_device *) cqr->device;
	if (irb->scsw.cstat == 0x00 &&
	    irb->scsw.dstat == (DEV_STAT_CHN_END | DEV_STAT_DEV_END))
		return dasd_era_none;
	
	cdev = device->cdev;
	switch (cdev->id.dev_type) {
	case 0x3370:
		return dasd_3370_erp_examine(cqr, irb);
	case 0x9336:
		return dasd_9336_erp_examine(cqr, irb);
	default:
		return dasd_era_recover;
	}
}

static dasd_erp_fn_t
dasd_fba_erp_action(struct dasd_ccw_req * cqr)
{
	return dasd_default_erp_action;
}

static dasd_erp_fn_t
dasd_fba_erp_postaction(struct dasd_ccw_req * cqr)
{
	if (cqr->function == dasd_default_erp_action)
		return dasd_default_erp_postaction;

	DEV_MESSAGE(KERN_WARNING, cqr->device, "unknown ERP action %p",
		    cqr->function);
	return NULL;
}

static struct dasd_ccw_req *
dasd_fba_build_cp(struct dasd_device * device, struct request *req)
{
	struct dasd_fba_private *private;
	unsigned long *idaws;
	struct LO_fba_data *LO_data;
	struct dasd_ccw_req *cqr;
	struct ccw1 *ccw;
	struct bio *bio;
	struct bio_vec *bv;
	char *dst;
	int count, cidaw, cplength, datasize;
	sector_t recid, first_rec, last_rec;
	unsigned int blksize, off;
	unsigned char cmd;
	int i;

	private = (struct dasd_fba_private *) device->private;
	if (rq_data_dir(req) == READ) {
		cmd = DASD_FBA_CCW_READ;
	} else if (rq_data_dir(req) == WRITE) {
		cmd = DASD_FBA_CCW_WRITE;
	} else
		return ERR_PTR(-EINVAL);
	blksize = device->bp_block;
	/* Calculate record id of first and last block. */
	first_rec = req->sector >> device->s2b_shift;
	last_rec = (req->sector + req->nr_sectors - 1) >> device->s2b_shift;
	/* Check struct bio and count the number of blocks for the request. */
	count = 0;
	cidaw = 0;
	rq_for_each_bio(bio, req) {
		bio_for_each_segment(bv, bio, i) {
			if (bv->bv_len & (blksize - 1))
				/* Fba can only do full blocks. */
				return ERR_PTR(-EINVAL);
			count += bv->bv_len >> (device->s2b_shift + 9);
#if defined(CONFIG_ARCH_S390X)
			if (idal_is_needed (page_address(bv->bv_page),
					    bv->bv_len))
				cidaw += bv->bv_len / blksize;
#endif
		}
	}
	/* Paranoia. */
	if (count != last_rec - first_rec + 1)
		return ERR_PTR(-EINVAL);
	/* 1x define extent + 1x locate record + number of blocks */
	cplength = 2 + count;
	/* 1x define extent + 1x locate record */
	datasize = sizeof(struct DE_fba_data) + sizeof(struct LO_fba_data) +
		cidaw * sizeof(unsigned long);
	/*
	 * Find out number of additional locate record ccws if the device
	 * can't do data chaining.
	 */
	if (private->rdc_data.mode.bits.data_chain == 0) {
		cplength += count - 1;
		datasize += (count - 1)*sizeof(struct LO_fba_data);
	}
	/* Allocate the ccw request. */
	cqr = dasd_smalloc_request(dasd_fba_discipline.name,
				   cplength, datasize, device);
	if (IS_ERR(cqr))
		return cqr;
	ccw = cqr->cpaddr;
	/* First ccw is define extent. */
	define_extent(ccw++, cqr->data, rq_data_dir(req),
		      device->bp_block, req->sector, req->nr_sectors);